Axure RP

Comments: Faster feature implementation

Pros: Axure makes interactive prototypes so easy, and has saved us millions of rounds of back-and-forth for people who "need to see the whole picture" or "feel the workflow end-to-end" before they can give feedback. There is not a substitute out there (everything else just creates hotspots and links). The support team and training materials are also awesome. This tool makes me so happy and makes me look professional as a UX designer. I've used it for everything -- from workflows to high-fidelity user-facing usability tests.

Cons: Axure is not a traditional design tool to replace high-fidelity photoshop mockups or sketch vector assets. Its implementation of master widgets do some of the things a designer might need, but it is still not the same as what you get with a final-asset tool that traditional designers would use. The mobile-responsive flow is also a little wonky sometimes. There are breakpoints you can design for but not fluid design states.

Comments: I've found this tool replaced my need for separate tools for wireframes, interactive mockups, etc. This is a truly encompassing tool with good forum support. It takes a couple of hours with an existing project to mock out a look and feel for new modules, things that would take my Dev team days to accomplish.

Pros: It's flexible and works if you want a quick wireframe or if you want an interactive functional demo. It's got good online support in forums and training videos and the price was much better than other tools I tried (like iRise).
It's fun to work in and build demos and the dynamic panels are tremendously powerful.

Cons: Ever want to review different color schemes for you mocks? Good luck. The one downside of Axure is that dynamic panels (which are wonderful) are essentially all spaghetti code. You build a different page and show it. Once you have a lot of pages a color scheme change isn't a simple css edit, it's hundreds of little changes made using the formatting bar...